SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '11c5cbb0e5f150579c3dfffddd2897ff005ada044302aec78d8006d030ab9af0' 
  AND token = 'lSqC6Rxr2gc+eclwyVJwSK+HH8UKm5wZef4vLgkV2j8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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