SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9632e681d19376501e1bae00fa37404209b709cfcb80958ba31bf967f82a73bb' 
  AND token = 'dTFPUTd7SDU+SE3+Fhg/Rvq+C7PaD9DJhwDluJPCzno=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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