SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '49315ad1e1102d61c81d0b8322988b048f815896e8743fa29f64447cc5f8b3a6' 
  AND token = 'xtmodqNrF5486uJazOTvYmcBcX2ZA4dZoZebm+66IGE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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