SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f19be88e574cf8acaff63edbfeba54385aafb5f7d722cb4faee2ba4bf98f9235' 
  AND token = 'mOwkwCtOO0kVU/AYXceNzBlO/SvLQwEqggKl3uKjhnk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}