SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cc1f256556090725dd35398d06ff4bed1a76a45bc2ddbe060a9ac4a1190183d5' 
  AND token = 'TjK1ICjJqVY+bcRPhE37Yl5h8/EBQ8f0vZdEsk6jMPw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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