SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5ac12b8e88a62286a4a6050d360dcfcd5d0c6e2b3251f7242620aa65b9b9806e' 
  AND token = 'kpAEUfyJjL9Yhfp0I2I8Or0Ax7yTE7PEuUXhPAe0Cbo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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