SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3ba520600d64353ff9f757ae2f79b2c94a0663b3912489b51f23b537d2617830' 
  AND token = '2ZZ79KlezOZKC/R5g8GMthTKyLjunlEQJVlQNq2Vj6s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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