SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '762dc8f5910eea4de7c9d44b5aa9cbd80da24be518f0bd504d75182d6ed298ef' 
  AND token = 'EmYHxCksoIdxcKUQxSEYK8DrBzWdDVuARLVbFm/s2ng=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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