SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'effa047bfa871ea995db31e47068089bac47fe8a010d2191d3be8fa4c1f29122' 
  AND token = 'nJqHUmXhzESoAKgUBHOzdPJn1xCSHVFzzUD+EK8uXgY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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