SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b0ef91e542c891031719d3b82621b70286b533b033b082f4b28ad3264a574caa' 
  AND token = 'HkDFkSG++lpgJMF9Mrrj77krTIaSykUs5liPoQjOnGU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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