SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f1c54a64c036a492c10b6b76dcb532c9e1dbbee4c06e2a8ce01d7070bfd36c0b' 
  AND token = 'EdfNoGA/7olWWobV1W3DX+Hvhq49cs/OTrZnsqbnou8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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