SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c55ee1dc4fb512962c1941f313abda3107c43cfa9271bbe47cd27a7895b4d67b' 
  AND token = 'Pe+mGMGd4XWA4kRlS54bH8IVjQ1Td3p2emaeXC7voEk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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