SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ac205a0d01be99c2ca6b00cde0e634cc5892a51f746413287e32e3f590b869b3' 
  AND token = 'HRU9qiY17rm6RXG2eFacGCTx8ueWCiBLcLOAWzqCFAQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00061

JSON explain

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