SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '7db6e33888f158062e9c2b88698eee5a7b4b114c601e47196169ab6dcf7a7bda' 
  AND token = 'DheJvVAvs1y+Y+W3QA1Z855zLQzQMKKoKA+YzAlMJZ4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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