SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'ead49409d7111ab91b1b04d9eb652b99d936efd5e8b03b7e0a7a9ce4ad1b065e' 
  AND token = 'vdV5Nl2OadZ38kNfRgtpi1cRpL3eDSiFv2btKn3VAg8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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