SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bcfc02f2fc757980e30613eaa39a39d05cfbccad5c3e969e594147c13d8005b6' 
  AND token = 'Jw/VRPvZFqBxr2a0sL0/GUsMpuy4rG2yNjEaRqqC0XQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}