SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '66150c6b39f208bcf3512320b73bfbaa4742c81fb62203d6ba04b0e47644d4a6' 
  AND token = 'q00NX9VULV+3QynDRPZw11unRam/ptWdtVLnpmGGhXA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00074

JSON explain

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