SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '19a9a1416dbcdf3d90ff6c783b9ad9a6a26a477ff078405a068f4113ac626d6b' 
  AND token = 'vS1U+jJ8rOKXt9QZcf5gVqFR6spY3A+Dggw9um34/38=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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