SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '823963945131f17a61409d3d0138c6e22f1b0894847b1f2c6270bd3c87b13dd9' 
  AND token = 'ODqaVQzauFYTPwyL4yeWKiV6KjzygU+qo+EfdWN7fh8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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