SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'db9b3f8023e46d2860312a9f46f7b72be53e8697e39dd629afeacb962ba4e0f0' 
  AND token = 'op1B5tnMdV7sZH6WgIfhN75JwPHtzc65zfSEqPdDaXo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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