SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2310da7bf60d0c0aeba314df1a17e2f36a649a3a428c01a77ee04979115769e8' 
  AND token = 'H+Ar57v5Jwn4Y75QEkXf2wMMCKWb+QDq2ssDzS7x4QI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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