SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ce19736e499aaeb8c63767879c6157962cde8c2ab60ab10055f1a7d88046d020' 
  AND token = 'BLxvmSUPJh9HMyzMzYW8pOGLDq2eBf5h/c/JYEo3ptM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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