SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5e0cd52057c3a2556cae467c370ba544563fc2689c81e745ebbf568b70de27d3' 
  AND token = 'kWRAKmlK/bsM/Xbci6puGy+/U0OhuufTFehKZPGAjtQ=' 
  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"
    }
  }
}