SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ee67d89e84c677e0396c8822ad7076185d2bcf829b52a459176c4fbcd73c1a03' 
  AND token = 'KoEbhnJAmL5ywIWDru1QZQi0mfKelz3TPmzMRpqhBIE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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