SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a31a2eb5f8469c875505fa525e5de21ea4fd67220e189249636716aecd0fbeca' 
  AND token = 'woNxIm3iG/Dp9+Da+dx3WaldvJ4TXB1+RKpjJ00mgZg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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