SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5620b251f8aef10f0786ce0e9a360289ef91b22862b03c09a582ed2fb37363ed' 
  AND token = 'dQnwZkQmvOtjytGIoWDkkiSGQkB/KTEa1MNN48slXJg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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