SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd18be6097cc316c7093abb74ec507747a7c14ebf3c5d1892379caf4eaf06a9be' 
  AND token = 'mcjUBpY0TY3+lsP2NaxXTnZq4JtFF+Um3MLV/LYfhXs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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