SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e6d55ccdf2f1925f3c05a4931c7b4fc306a9012b859642e92b6a9c83e058ec3e' 
  AND token = 'CkSqAKwFr8vSvlnYCX+mzy2ghZwnzR2goxc7brXxzOw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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