SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '544f96eecea4153269de9e84c224e11b4339b5f4f4b79ed05ae448e05c128192' 
  AND token = 'yEvREBLNnKV7cv73+2X1OxfDbV4vMlOyqYfe4pVv6YQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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