SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c2687a467d9302f5c02d3b043873b2ae2fb4716606368a6abccbc07a64b6480a' 
  AND token = 'AUSsmXClhYsNnin9VAkpSpLEKQwZzJ5qd/HSR/liO+w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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