SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a72fdbdd3ddef1fedd3ee2f5f9ca4fe97454919fd397a7444e5a24e4fccfeb5b' 
  AND token = 'Kio6n8BNI75gHrg6CJqmxW60RsB2p3Aln6ukoWWEjx8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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