SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'be7bbb44640fe20559349819c9d416a23c94ed66327d9fd4747687566aea46d9' 
  AND token = 'o+hvmEHkrhxau9kRLUwaYaGJMoUpZOcber+fLjKzP/c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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