SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e8f59de747926c6da9ec9b082d0ed82d1ce02f1943c03c550b32e4e0a4281725' 
  AND token = 'icN224zVsO6YUZChvUUtoGzqTOqrjDjXTZqFjglhHBg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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