SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'cca6fd59fb01e68b7c63564d815815f2cec20527eabe3053cff37f0bfd7aa7c2' 
  AND token = 'a8CI8xGQReB5s4pVsTdU5tezsJlpkvs5PFIsZfy46ag=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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