SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3066884802e2fd42090b7830ac3574d4db6ba742a27bec4dcad9ee8922865d3e' 
  AND token = 'yf1HudW8HKR01geG/VPVIFv4mmEDrmD/3rJyDr4LA7Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00051

JSON explain

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