SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'eb68e2b299f8af300d8b5edbbdfa4bef8a0b0b612b0195570139bcad4a5862d2' 
  AND token = 'Ct5Rp7GgtlzKMfcT9eok/J/pjbuU5SvnQJoDuP/6l40=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}