SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f0be4d22a65f9c7f702aaed1e114b1975bd1d3c8ea0b083022b9f010d57725cc' 
  AND token = 'O+zp/KCax5PyqFMDznJxky3KSYsjRdrHqLU3Bj0rvmU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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