SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '1edb9d637f0e56867518a948607599ed07e000aa3f73a931765653fcacdcbafe' 
  AND token = 'Kg0q1tY/rhS3q0aVVFuSmXxuKzV52jyEv+1G7Ai8Qyw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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