SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f88d79232f7ca86737cd73b4f6c4d2060cb6b7cc91fb46603be8c43ced4195f0' 
  AND token = 'XpxvZND/3b3btJeZNHbfR/m14wkYAfrC2DIgzMw9ZTo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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