SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e16a82f421f4bbf81aecfa213e3081a553fa0d54455d088eda4ff94784252ded' 
  AND token = 'gNDNkhmhMSegFD4z3c/UsRdgbRXjhJ267xVcFzW7Ww8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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