SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '8f88026bcfa8bc5685041d105385366c644101bfe512cb85ca9619c151b681e3' 
  AND token = '28x3Oa2jL1IyV0nSHD6HbT51i7YD+fp3TJ+gNqYxd7I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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